Seed Hawk Raven 2012 - Manual (Page 166)

Chapter 8
154 Seed Hawk® Viper Pro™ Installation & Operation Manual
Prescription maps used with the Viper Pro must be in the shapefile format and must be created using GIS
(Geographic Information System) software capable of creating shapefiles. These shapefiles must be in the
polygon shape format that complies with the ESRI (Environmental Systems Research Institute) shapefile
specifications. Shapefiles must also be in the WGS84 datum.
For best results, prescription maps used with the Viper Pro should contain as few rate zones as possible. Maps
with too many zones may affect performance of the field computer during the application. Raven recommends
that the smallest zone(s) contained within the prescription map should be no smaller than the width of the
boom or implement applying product.
For Example:
If the machine swath width is 90 feet [27.4 m], zones on the prescription map should be no less than 90 feet
[27.4 m] wide.
To load a prescription map shapefile onto the Viper Pro, the .shp, .shx and .dbf files must be copied into the
RxMaps folder on the USB flash drive used with the Viper Pro. Refer to the Uploading Prescription Maps from
a USB Flash Drive section on page 203 for detailed instructions.
Prescription (Rx) Map Look-Ahead
The prescription map look-ahead value is the number of seconds (determined by vehicle speed) which the field
computer is allowed to scan in front of the current vehicle position to find rate changes on a prescription map.
This feature may be used to help compensate for the time it takes a valve to fully adjust to a different rate.
For Example:
If the control valve takes four seconds to adjust to a rate change, set a prescription look-ahead value of 2
seconds to allow the field computer to begin adjusting the valve prior to the vehicle entering the new rate
zone.
Note:
The prescription Look-Ahead value only affects products controlled in reference to a prescription
map.
1. To access the prescription map look ahead value from the Viper Pro main screen, touch Menu, then Setup,
Maps, Rx Map, and Look Ahead. The Rx Map menu is displayed.
2. Touch within the look-ahead seconds field and use the on-screen keyboard to set the desired look ahead
value.
3. Touch OK to save the new look-ahead setting and return to the Viper Pro main screen.